UKHAS Wiki

UK High Altitude Society

User Tools

Site Tools


ideas:flight_support

Differences

This shows you the differences between two versions of the page.

Link to this comparison view

Both sides previous revisionPrevious revision
Next revision
Previous revision
ideas:flight_support [2006/07/09 22:37] rocketboyideas:flight_support [2013/05/07 07:55] (current) – [Radar Reflector] rocketboy
Line 1: Line 1:
 ====== Flight Support ====== ====== Flight Support ======
 +
  
 ===== Radar Reflector ===== ===== Radar Reflector =====
Line 9: Line 10:
 {{:ideas:corner.jpg|:ideas:corner.jpg}}  {{:ideas:corner.jpg|:ideas:corner.jpg}} 
  
-Size - in order to work effectively each side of the corner must be at least 1.5 wavelengths this gives a size of about 15cm to cover down to S band RADAR (3GHz = 10cm wavelength) - this makes a suitable reflector about 30cm (1 foot) tip to tip. +FAR101 says "the reflector will present an echo to surface radar operating in the 200 MHz to 2700 MHz frequency range". 
 + 
 +Size commercial radiosonde radar refelctors are about 50cm tip to tip. 
  
 A very lightweight reflector (less than 30g) can be constricted using carbon fiber kite spars and metalized plastic foil (as used in space blankets).  A very lightweight reflector (less than 30g) can be constricted using carbon fiber kite spars and metalized plastic foil (as used in space blankets). 
  
-Can anyone confirm that aircraft radar (airborne and ground based) is S band or higher?  
      
  
Line 19: Line 21:
  
 This device is used to detach the payload from the balloon (or release items attached to the payload). Its an igniter (used in amateur rocketry) inside a small hard plastic tube (sealed with epoxy at both ends) - when fired the igniter has enough explosive force to shatter the tube (and hence release the balloon) - it works a treat in all the tests I have done, including some at -30dec C and in a vacuum chamber. This device is used to detach the payload from the balloon (or release items attached to the payload). Its an igniter (used in amateur rocketry) inside a small hard plastic tube (sealed with epoxy at both ends) - when fired the igniter has enough explosive force to shatter the tube (and hence release the balloon) - it works a treat in all the tests I have done, including some at -30dec C and in a vacuum chamber.
 +
 +__**WARNING: wear full eye area wrap around safety goggles when testing these devices.**__
  
 {{:ideas:release.jpg|:ideas:release.jpg}} {{:ideas:release.jpg|:ideas:release.jpg}}
Line 25: Line 29:
 The igniter needs about 2amps @ 3Volts for just a few milli seconds to fire - it can even be fired from a charged 4700uF capacitor. The igniter needs about 2amps @ 3Volts for just a few milli seconds to fire - it can even be fired from a charged 4700uF capacitor.
  
-{{:ideas:cct.gif|:ideas:cct.gif}}+{{ideas:cct0.gif|}} 
 + 
 +The ignitor on the right hand side of the circuit can be replaced by a small 6V bulb for testing - the bulb will light briefly when fired. Once you are happy with the circuit try an igniter. 
 + 
 +[''adeptium/STARS Project''Not happy about the use of a wet cap for near-space use, but Farnell supplies an AVX 3300uF tantalum, 4-10V operating range, rated to -55C with no loss of capacity I'm going to try with one or two of these.]
ideas/flight_support.1152484622.txt.gz · Last modified: 2008/07/19 23:30 (external edit)

Donate Powered by PHP Valid HTML5 Valid CSS Driven by DokuWiki